30$ 6max J9o vs unknown

just fold river. fish do this with trips+

I would call river for half pot obv

i dont agree with calling turn.

i agree with checking the flop since we dont have any important information about strength of our opponents range. But this changed on the turn after he minbet into us. On the turn we should actually fold 0% of our range and we have to defend our passive line by rasing a lot of hands. Since our checking range on the flop doesnt consist many hands that we can raise for value on the turn (55, QcJc), we need to raise medium strength hands aswell.
so in this situation i am raising turn to 80 to defend my passive lines.

as played you came to the river with too many weak hands that cant stand further agresion, you are being exploited smartly by big bets and there is almost no way for you to make EV decision with your range.

so in my opinion, you missplayed this hand on the turn and get to the river with too wide range and gave your opponent too much fold equity too often.

Well if we read his minbet on turn very likely as hand we beat already then bluff catching river would start to be reasonable. Which I did this time.

We can get value from some draws by raising, but better hands wont fold and air hands fold. Plus we do have gutshot also if we are behind so not really hand I want to raise-fold.

..so not really hand I want to raise-fold.

i disagree with this statement.
3rd pair + gutshot is EXACTLY hand you want to raise / fold. this hand is SO weak vs your opponents range. like there are almost no good river cards for you. your outs that complete your hand have big reverse implied odds since they are only 2nd nuts. if you hit Q on river, villain could have AJ. If you hit J for 2pair, villain can have str8. Every club is bad for you. Like you dont even understand how many bad river cards are there for you and for your insanly weak range.
i am 99,9% sure that raise/folding turn is only correct way to play this hand and that our equity is small when facing agresion but it is good enough to make a stab on the turn and check back many river cards.

I think main question in this hand is how often we assume to face such big bet in river. Versus unknown I am happy to call most rivers versus small bets as they can do it with worse made hands as value or have some A3 or whatever. I would say such overbet situation is rare.

I dont see our gutshot to have much of negative implied odds. Villain can have AJ, but its very small part of his range plus even if I hit second best straight I am not looking to get allin versus unknown when there is such obvious straight possibility in board. But villain might also tet to bluff it when board looks scary.

So do we want to just call turn to induce bluff (or value bet from worse), which most of time is not overbet or raise turn and hope for free river and get value from drawing hands. Villain is likely not folding any better made hand in turn.

I think main question in this hand is how often we assume to face such big bet in river.

awesome question.

in this situation we are facing turn probe bet.
definition of probe bet is: A bet made primarily to gain information by gauging opponents' reactions, especially a small bet.

so i filtred for all my hands played where i was facing turn probe bet and i had opportunity to make a raise and try to find out how often when i call the bet our opponent continued with big river bet.

there were some hilarious hands like for example this one:

http://www.handconverter.com/hands/2382206

but actuelly my opponents did line: call pre, check flop, probe turn, big bet river on only 35% of river cards. the other times they check with marginal showdown hand or completly gave up and went to showdown with 7high or few times they tried desperate bluff with smallish sizing.

so by calling turn probe bet on turn we will be facing big bet on river in about 1/3 times.

so i believe with this information in mind we should not be happy about calling turn with wide range of hands so i believe raising turn is very reasonable strategy. if my opponent is making a bet to gain information, i will gladly give him information that my hand is strong and take down the pot.